Our goal is to discover those processes involved in the transport of odorous substances to and away from the receptor sites on the olfactory sensory neurons. It appears that odors entering the vertebrate nose stimulate the release of secretory granules from sustentacular cells and modify the endogenous activity of cilia on the receptor cells. The objectives of this study are to determine the processes responsible for granule release, to determine the mechanisms responsible for changes in ciliary action, and to find the relationships between these events and the resulting initiation of neural activity. We will determine the effects of induced changes in organelle activity including blockade of the secretory process and of ciliary motion on the sensory response measured electrophysiologically and behaviorally. The chemical properties of the granule material will be studied with respect to its affinity for adorous substances.